Supply of ammunition to freely rotatable gun turrets



Sept. 27, 1949. E. c. M. DASSlS-FONSECA ETAL 2,483,334

SUPPLY OF AMMUNITION TO FREE'LY ROTATABLE GUN TURRETS Flled Dec 18 1945 2 Sheets-Sheet l ZZZ/Yd (707m, 57

' Sept. 27, 1949.

E. Q M. DASSlS-FONSECA ETAL ,483,334

SUPPLY OF AMMUNITION T0 FREELY ROTATABLE GUN TURRETS Filed Dec. 18, 1945 2 Sheets-Sheet 2 Patented Sept. 27, 1949 SUPPLY OF AMMUNITION TO FREELY .ROTATABLE GUN TURRETS Evelyn Cecil Muschamp dAssis-Fonseca and John Wotton, Bristol, England, assignors to The Bristol Aeroplane Company Limited, Bristol, England, a Britishcompany Application December 18, 1945, Serial No. 635,658 In Great Britain December 19, 1944 '7 Claims.

This invention concerns improvements or relating to gun turrets andto the supply of ammunition thereto.

kind which are .capable of ,continuousrotation in either/or both directions ,of traverse. K

In gun turrets of this kind the supply of ammunition is usually carried within the turret so that it rotates therewith; Although in this way no twist is imparted to the belt upon rotation of the turret the quantity ofammunition carried is governed by the space available instead of by operating requirements. Moreover, disposing the .ammunition in the turret increases the Weight of the installation so that traversing motors of greater power. are required. 7

By disposing the ammunition supply. outside the turret these disadvantages are overcome. Furthermore, when the turret is carried in an aircraft the ammunition supply may be disposed at about the centre of gravity of the aircraft so that the latter is, not unduly affected by the quantity of ammunition provided. With a view to overcoming the above disadvantages it has heretofore been proposed to provide for feeding portion of the ammunition belt therebetween) an ammunition belt into the interior of a rov tatable gun turrent from a storage outside of said turrent the ammunition belt being led'into V the turret by a path which lies along the axis of rotation of the turret, the ammunition belt passing through a pair of spaced guides one of which is fixed and the other of which is rotatable with the turret the arrangement being that rotation of the turret causes twisting of the belt in, and only in, the length of the belt between the two guides. With this proposed arrangement the degree of rotation of the turret is limited by the amount of twisting which may be imparted to the belt between the two guides so that the proposed arrangement is impracticable when the gun turret is of the kind above set forth which is capable of continuous rotation in either or both directions of traverse.

The present invention has for its principalobject to provide a gun turret of the kind set forth in which the ammunition supply is outside the being resisted by meanswhich is permittedtov return the belt when the belt haslbeenitwisteds 2 through a predetermined angle or to a predetermined position.

According to another aspect of the invention means for feeding an ammunition belt into a turret of the kind set forth is characterised in that the ammunition belt approaches the turret along a chute which is twistable from a datum position against the action of a restraining agent and disengageable means is provided to couple said supply chute to the turret for rotation therewith, said coupling means being automatically disengaged when said chute has been twisted through a predetermined angle from its datum position whereby the supply chute is returned toits datum position and said coupling means is automatically re-engaged.

According to another feature of the present invention means for feeding an ammunition belt to a turret of the kind set forth comprises an ammunition chute carried by and rotatable with the turret, a supply chute for leading an ammunition belt to the turret (said supply chute which is capable of being twisted through a predetermined angle from a datum position being spaced from the turret chute to accommodate a turret in accordance with this invention located on the upper surface of the fuselage of an aircraft;

Figure 2 is a sectional elevation of the belt aligning mechanism;

Figure 3 is a section on the line 3-3 of Figure 2; and

Figure 4 is a view of a portion of the belt of ammunition which is fed into the turret.

Referring to Figure 1: the gun turret is generally indicated by the reference numeral 5 and is mounted on the upper surface of the fuselage 6 of an aircraft, the turret being supplied with ammunition from a source of supply 1 located outside the turret and within the fuselage. A single belt of ammunition passes from the source of.supply l b means of chutes 8 and H to the turret 5 and entering the latter passes upwardly towards a cannon machine gun 9. The chute 8 extends from the ammunition box 1 to beneath the turret 5 where it is anchored (as at ID) to the fuselage B at a point disposed on the axis of rotation of the turret. The chute II which is capable of being twisted with rotation of the turret extend along said axis from the anchor point It to the bottom of the turret: this is the supply chute mentioned above. The ammunition belt is conveyed to the turret and after passing into the latter is conveyed along another chute (the turret chute l2) to the machine gun 9.

The present invention contemplates permitting the supply chute H (and hence the ammunition belt therein) to be twisted by the turret about its anchorage it from a datum position through a complete circle whereupon the chute H is automatically untwisted and brought back to said datum position. For convenience it will be assumed that said datum position is that in which the long axis of the rounds of ammunition in the supply chute ll point fore-and-aft of the aircraft. When the chute i l is in this datum position the gun 9 will also be pointing fore-and-aft of the aircraft, the turret 5 being in its datum position. Figure 1 shows this arrangement in which therounds of ammunition in the chute l l are in their datum position pointing fore and aft, the gun 9 being similarly directed.

The construction and operation of the beltaligning device will now be described with reference to Figures 2 and 3. The upper end of the supply chute H is attached to a guide l3 which is carried by a disc M rotatably mounted in the bottom of the turret. The disc M is co-axial with the axis of rotation of the turret 5 and is carried upon anti-friction bearings l5 disposed between the disc and the floor It of the turret. A drum l! is bolted (as at It) to the disc M and extends downwardly therefrom beneath the turret. The drum l! is provided with a bracket i 9 which carries a pair of rollers 20, while a platform 25 secured to the fuselage carries a pair of co-operating rollers 22. A steel cable 23 passes between the pair of rollers 20, 22 to engage at one end with a spring 24 mounted upon the platform 2i and at the other end with the rollers 28 by means of the nipple 25. The spring 24 is pretensioned to a certain extent so that a pull is always transmitted by cable 23 to the rollers 26 and hence to the drum I! thereby tending to maintain the latter in a predetermined position. As a consequence the disc I 4, guide 13 and the upper end of the supply chute Ii are urged towards this predetermined position, which is the datum position referred to above. In the event that the disc-drum unit M, ii is rotated in either direction the spring 24 is compressed, the cable 23 passing over the pulleys 22 and between the pulleys 26 during rotation thereof with a minimum of friction and the spring will urge the disc-drum unit to return to the datum position.

The drum I1 is formed with an arcuate slot 26 with which there is associated a plunger 21 carried by the floor I6 of the turret 5. The plunger 2! is urged by spring 28 towards the drum I'i so as to enter into the slot 26 and carries a roller 29 which is capable of co-operating with a ramp 38 secured to the platform 2! It will be appreciated that when the plunger 27 passes through the arcuate slot 26 rotation of the turret 5 will be transmitted from the floor l6 thereof to the plunger 2'! which, engaging with either end of the arcuate slot, imparts rotation to the drum l1 and hence to the disc M, guide I3 and the supply chute H. Such rotation will be resisted by the spring 24. When, during rotation of the turret, the roller 29 is brought into engagement with the ramp 30 the plunger 2! will be withdrawn from the arcuate slot 26 and as a consequence the turret 5, floor l6 and plunger 2'! are free to rotate independently of the drum ll, disc I4 and supply chute Ii. As a conseuence, the disc-drum unit M, H is capable of being returned to its datum position by the spring '24 irrespective of the rotation which is being imparted to the' turret 5.

When the supply chute l l is in its datum position so that the rounds of ammunition therein and the gun 9 points fore-and-aft of the aircraft the roller 29 is at the crest of the ramp 30 and plunger 2'! is in its retracted position and midway between the extremities of the arcuate slot 26. Upon rotation of the turret 5, in either direction, the roller 29 is moved down the ramp 30 and the plunger 21 moves towards the drum When the roller 29 disengagesthe ramp 30 the plunger 21 has entered the slot 23 and is 7 therefore in a position to engage with the extrem- I ities of the slot. Thereafter, further rotation of the turret brings the plunger 21 into engagement with one end of slot 26 and as a consequence disc [4 is carriedaround with the turret. When the turret describes a complete circle from its datum position the roller 29 is once more at the crest of the ramp 30 with plunger 21 disengaged from slot 26. Upon disengagement of the plunger 21 from the slot 26 the disc M and sup ply chute l i are rotated by return spring Mgr-elatively to the turret 5 back to the datum position of the chute. This position is shown in Figures 2 and 3. It will be clear from Figure 3 that when the supply-chute H has been re-aligned as described, the roller 29, and plunger 21 have been.

returned to the positions indicated above so that with continued rotation of the turret the plunger 21 is again brought into engagement with the drum ll by entering slot 26.

For the effective operation of the device described above it is essential that at the end of a re-aligning operation the slot 26 be brought to a position in which the ends thereof are disposed one on each side of the axis of the plunger 21 irrespective of any movements of the turret which may take place away from its datum posi- U tion during that time in which the supply chute H is being untwisted. For instance, at the moment when the plunger 2'! is withdrawn from in one direction up to its datum position (at' which this release is efiected) may at the moment of release commence rotation in the opposite direction. Under these circumstances the plunger 21 is moving away from the datum position'to which the drum I1 is being returned. To ensure that in this, and in all other cases, the slot 26 assumes a position such that it will definitely be re-engaged by the plunger 2'! after the supply chute H has been returned to'its datum position, the length of the arcuate slot 26 is selected so that the turret at its maximum rate of traverse will move through less'than half said length in the time which is required for the supply chute to be returned to its datum position.

The plunger 21 will enter the slot 26 when the turret has moved over a portion of the are defined thereby and it will only be after further rotation of the turret in the same direction that the plunger will engage with one end of the slot ing its return to the datum position.

2|: and commence imparting a twist to the chute I The turret chute l2 which conveys the ammunition belt to the gun 9 is secured at its lower end to a guide 3| which is supported by a structure 32 carried by the floor It of the turret 5. As is clear from Figure 2 the turret chute i2 is coaxial with the supply chute and the guide 3| is spaced from the guide I3. During rotation of the turret 5 from its datum position a twist is imparted to the ammunition belt lying within the supply chute whilst the portion of the ammunition belt within the turret chute 2 remains untwisted and the portion of the belt between the guides l3 and 3| has imparted to it only the slight twisting due to movement of the turret to bring the plunger 2'! into engagement with one end of the arcuate slot 26. However when realignment takes place the consequent untwisting of the supply chute subjects the length of belt between the guides l3 and 3| to a corresponding twist of one complete revolution. It is therefore necessary to enable rotation to take place between that portion of the belt associated with the supply chute and that portion of the belt associated with the turret chute I2. To this end the belt (which is generally indicated by the reference numeral 33) comprises rounds of ammunition 34 which are connected together by links 35 that permit adjacent rounds of ammunition to be twisted relative to each other through a complete turn. The links 35 which permit this relative movement are of known construction and each comprises a single-arm clip 33, a double-arm clip 31 and a rivet or the like 38 which secures 1 the two clips together and permits pivotal movement thereof (see Figure 4).

Since the guide |3 associated with the rotatable disc l4 and the guide 3| associated with the turret chute l2 are spaced apart (as shown in Figure 2) when the supply chute II is re-aligned that portion of the ammunition belt which is associated with said chute will be rotated through a complete circle relatively to that portion of the ammunition belt which is associated with the turret chute l2 this being permitted by the connection of the single and double-arm clips by the rivet 38.

Since the rate of ammunition supply to the turret 5 is high compared with that at which the supply chute l is realigned, a circumstance may arise in which the portion of the ammunition belt 33 associated with guide I3 is drawn into engagement with the guide 3| before realignment is completed. In such an event the round of ammunition lying somewhat transversely of the rectangular mouth of the guide 3| would press against the lower edge thereof and prevent the ammunition belt from passing to the gun 9. To prevent this occurrence a firing cut-out switch 40 is provided in the circuit to the electric firing gear of the gun 9, the said switch being operated by a trigger 4| carried by the plunger '27. The arrangement is that the switch is opened when the trigger 4| is moved away therefrom and this occurs when the roller 29 is brought into engagement with the ramp 3i! so that the firing circuit is broken and the belt of ammunition 33 ceases to be drawn towards the gun 9 and across the space between the guides l3 and 3| when the supply chute l is freed from the turret 5 and dur- In the event that there is associated with the gun 9 an electrically driven stripper mechanism of known construction for separating the links 35 from the rounds of ammunition the switch 40 will also be associated with the electric driving motor for the stripping mechanism so that when realigning is commenced the firing circuit of the gun is interrupted and simultaneously the electric motor of the stripper mechanism is rendered inoperative.

To ensure that the ammunition belt is stopped in such ,a position that a rivet 38 lies within the space between the guides l3 and 3| the stripper mechanism incorporates a locking device which is spring urged to its locking position and is solenoid operated to its retracted position. The solenoid is in the circuit of switch 40 so that when the latter is actuated the locking device is urged to its operative position-where it halts the stripper mechanism with the belt in the selected position relative to guides l3 and 3|.

We claim:

1. A device of the kind set forth comprising a gun turret, a belt of ammunition, a source of supplly of ammunition disposed outside the turret, chute means for conveying the ammunition belt from said source of supply into said turret, means for twisting the chute with rotation of the turret, means for resisting the twisting of said chute and for returning the chute to its untwisted position when the chute has beentwisted through a predetermined angle.

2. Means for feeding an ammunition belt into a turret of the kind set forth characterised in that the ammunition belt approaches a turret along a supply chute which is twistable from a datum position against the action of a restraining agent and disengageable means is provided to couple said supply chute to a turret for rotation therewith, said coupling means being automatically disengaged when said supply chute has been twisted through a predetermined angle from its datum position whereby the supply chute is returned to its datum position and said coupling means is automatically re-engaged.

3. Means for feeding an ammunition belt to a turret of the kind set forth comprising a turretammunition chute carried by and rotatable with a turret, a supply chute for leading an ammunition belt to a turret, said supply chute being capable of being twisted through a predetermined angle from a datum position and being spaced from the turret chute to accommodate a portion of the ammunition belt therebetween, means for disengageably coupling the turret-end of the supply chute to a turret and means for returning the supply chute to its datum position.

4. Ammunition-belt feeding means as claimed in claim 3 in which the chute-returning means comprises a spring or the like which urges said supply chute to maintain its datum position,

5. Ammunition-belt feeding means as claimed in claim 3 wherein said disengageable coupling means comprises a catch member carried by the turret, a pair of spaced catches associated with the chute, either of said catches being engageable by the catch member to rotate the supply chute by the turret and means carried by the turret mounting engageable by said catch member to disengage the latter from said catch at the datum position of the supply chute.

6. Ammunition-belt feeding means as claimed in claim 3 in which said turret-ammunitionchute is spaced from said supply chute by the length of belt between a pair of adjacent links of ammunition belt.

'7. Ammunition-belt feeding means as claimed in claim 3 in which there is provided a switch which is operated by said means while the sup- 2,483,384 ply c-h-ute is uncoupled from the turret to inte-r- UNITED STATES PA'IENIS rupt the firing of the gun.

Number Name Date EVELYN CECIL MUSCHAMP I I D,ASSIS FONSECA 2,329,308 Trotter et a1 Sept. 14, 1943 JOHN WOTTON. 5 FOREIGN PATENTS Number Country Date REFERENCES CITED 355,767 Great Britain Feb. '21, I930 The following references are 'of record in the file of this patient: OTHER REFERENCES 10 Flight Magazine, Feb. 4, 1943. 

